The Audi A4 Avant exists because not everyone wants an SUV and, while BMW’s 3-series has the ‘medium premium’ saloon market sewn up, when it comes to wagons Audi rules the roost. And with this Avant version of the new A4 that domination looks set to continue.

It’s no great mystery as to why this is so. While the 3-series’ sporty character suits the saloon sector, Audis are seen as sensible, dependable and quietly luxurious – themes that sit perfectly with this more family oriented corner of the market. Indeed, Audi claims the A4 Avant commands over 40 percent of its segment, while BMW and Mercedes squabble over much smaller shares.

The new model is certainly going to tick all the right boxes for the aspirational middle classes. With a sleeker, fastback look reminiscent of the A6 Avant the A4 at least looks significantly different from its predecessor. Well, compared with the saloon version at least. It’s still pretty conservative of course, but then that’s the Audi way.

Audi A4 Avant: the estate we're in

Much cleaner in appearance than the 3 Series or C-Class estates, the Avant’s initially low key design merits closer examination and will delight the aesthetically literate. Witness the so-called ‘tornado line’ originating in the headlights and then sweeping over the flanks and breaking up the surface, reversing around the rear light to create a subtle airflow-splitting lateral spoiler. Form and function? Again, Audi fundamentals and brilliantly executed.

The A4 Avant is bigger than its predecessor, 154mm of the 166mm wheelbase stretch pushing the front axle forward to improve handling balance. It’s also 55mm wider and 117mm longer overall, boot space increasing by 48 litres to 490 litres seats up and 1430 litres folded. Only the C-Class estate is bigger, with a maximum of 1500 litres available.

Practical features abound too. There’s a neat reversible floor, rubberised on one side if you’re carrying muddy hiking gear or have a bootful of bounty from the garden centre, and optional load restraints seen previously on the A6 Avant. It’s comfy too, with firm, supportive seats and lots of useful cubby holes in the cabin.

Ok, so much for practicality – what about the technology?

Luddites and technophobes need not apply – the A4 Avant boasts Vorsprung Durch Technik with the emphasis on the Technik. For the driver this means Audi’s button-heavy Multi Media Interface (MMI) to control the various navigation and media options, including the very slick iPod interface. All cars get a 6.5-inch colour screen, MP3 compatible CD player and 10-speaker stereo, the options list offering all manner of further goodies according to taste and budget.

The electronic automatic handbrake is another typical example of Audi’s fixation with replacing traditional mechanical components with sophisticated technology but this is only the start of it. The optional Audi Drive Select system offers three-way adjustment for throttle response, steering assistance and – if fitted – CDC (continuously damping control) settings. With MMI there’s a further personalised setting available, with different drivers able to store their own settings on different keys.

You can also choose from three levels of parking assistance, automatic cruise control, brake assist, blind spot warning alerts in the mirror housings and even a vibrating steering wheel to alert you to ‘unintentional’ lane changes. We’re not quite at the stage of electric shocks for forgetting to use your indicators but this can’t be far off.

Enough already! What about the engines?

The techfest continues under the bonnet. When the A4 Avant arrives in June 2008 there will be five engine options. The 1.8 TFSI petrol has already impressed in the A4 saloon and if you can’t kick the big-cube habit there’s also the familiar 261bhp direct injection 3.2 V6. Diesels start with a 141bhp version of the new common-rail 2.0 TDI, with 118 and 168bhp versions to follow. Two diesel V6s are also on offer – 2.7-litre (187bhp) and3.0-litre (237bhp) – if you need more grunt.

The 2.0-litre TDi driven here will account for most Avant sales and is a step up in terms of refinement from the outgoing PD diesel motors. An output of 149g/km CO2 and a claimed combined average of 49.6mpg are decent enough for it to qualify as the default choice. But it’s still eclipsed by both the 318d and 320d versions of the 3 Series Touring in terms of CO2 and fuel consumption.

Don’t overlook the petrols though, the four-cylinder TFSI motor is especially impressive. The 178bhp 2.0-litre version we drove proved smooth and eager, the exhaust side Audi valvelift system providing a big step up from the 1.8 and delivering peak torque of 236lb ft from just 1500rpm. Six-speed manuals are the default, with optional CVT gearboxes for front-wheel drive cars and six-speed autos for the flagship V6 and Quattro models.

Ok, engines sorted, but is there a bit of R8 magic in the handling?

Not quite. When Audi encounters a development challenge the default reaction appears to be to throw technology at it, rather than perhaps address the issue at its core. And when it comes to the chassis it seems there is still a lot to learn from direct rivals Mercedes and BMW.

Three-quarters of A4 Avants are expected to be front-wheel drive versions and despite moving the front axle further forward and coming up with a complex five-link front suspension design the traditional nose-heavy handling is still apparent. It’s not helped by a chassis that becomes further unsettled as you attempt to correct. There's also a lack of feel at the steering wheel.

Sports suspension lowers the chassis by 20mm, S-line dropping it a further 10mm and throwing 18-inch wheels into the mix too. Ride comfort suffers as a result but some semblance of poise is the reward, the optional Audi Drive Select at least allowing some choice between tough and tender when specced with CDC dampers. Forget the variable rack, variable assistance dynamic steering too – it may be technologically impressive but feels totally artificial.

Verdict

While the traditional demarcations between the big German three of Audi, BMW and Mercedes are now more blurred than ever some constants do remain. And if you consider yourself an Audi buyer through and through the A4 Avant is satisfyingly on message. However it won’t win any converts from the two main rivals.

Audi insists its customers demand and expect high levels of innovation and enjoy exploring the technological features on offer. But at times it feels like the engineers have lost sight of the real issues and the A4 feels too clever by half. Get the basics right and the rest will follow guys.

Of course, for many issues of desirability and liveability weigh in much more heavily than knife-edge handling and in this respect the A4 Avant has to be considered a success. Handsome, swift and with a great engine line up to back up its practical nature there’s little reason to doubt it will build on the success of its predecessors.